Celine Dion’s sister Claudette Dion said that the singer has been struggling to find treatment for her stiff person syndrome diagnosis.

During an interview with Le Journal de Montreal, Claudette revealed that despite working with “the top researchers in the field,” the Grammy winner, 55, has seen little improvement in her health.

“We can’t find any medicine that works, but having hope is important,” Claudette said.

According to the National Institutes of Health, stiff person syndrome is a “rare, progressive neurological disorder” that can cause stiff muscles in the torso, arms and legs.

It affects about one in a million people.

Following the diagnosis, Celine was forced to cancel her Courage World Tour, which Claudette said was necessary for her chances of rehabilitation.

“I honestly think that she mostly needs to rest. She always goes above and beyond, she always tries to be the best and top of her game,” she said. “At one point, your heart and your body are trying to tell you something. It’s important to listen to it.”

Their sister Linda has since moved into Celine’s Las Vegas home to act as a caretaker for the hitmaker.

“When I call her and she’s busy, I speak to my sister Linda who lives with her and tells me that she’s working hard,” Claudette explained. “She’s listening to the top researchers in the field of this rare disease as much as possible.”

Despite the lack of improvement in Celine’s condition, the family still has “trust” that things will get better.

In May, the “My Heart Will Go On” songstress announced “with tremendous disappointment” that she was cancelling over 40 of her tour dates due to the debilitating disorder.

“I’m so sorry to disappoint all of you once again. I’m working really hard to build back my strength, but touring can be very difficult even when you’re 100%,” she wrote via Instagram.

“It’s not fair to you to keep postponing the shows, and even though it breaks my heart, it’s best that we cancel everything now until I’m really ready to be back on stage again,” she continued.

“I want you all to know, I’m not giving up… and I can’t wait to see you again!”

While she was revealed her diagnosis with the disease in December 2022, the singer said at the time that she had been “dealing with problems with [her] health for a long time.”

The “Because You Love Me” artist previously had to delay her Las Vegas residency in October 2021 after experiencing “severe and persistent muscle spasms.”

While she was eventually able to return to the stage, it’s unclear when — or if — Celine will be able to perform again.